1. Field of the Invention
The present invention relates to a solar cell-bearing roof comprising a solar cell module for a building and a method for installing the roof. The present invention also relates to a building comprising the solar cell-bearing roof and a power generation system comprising the solar cell-bearing roof.
2. Related Background Art
In recent years, earth warming phenomenon due to fumes emitted from the steam-power plants, fear of fossil fuel being exhausted, and radioactive contamination due to accident at or radioactive waste from the atomic power plants have been internationally discussing in terms of the earth. And the public concern about the global environment and energy has been rapidly increasing.
Under this circumstance, public attention has now focused on and various studies have been made on the power generation system using a solar cell since it has advantages: it is a clean power generation system which is free of the problems relating to radioactive contamination, earth-warming and environmental pollution, the sunlight to be used as its energy source reaches everywhere on the earth, there is no problem for the energy source to be localized, and it is expected to be a future power generation source.
As such a power generation system, there have been a variety of solar cell modules which can be installed on a roof of a building. Some of them have been practically used.
In order for such a solar cell module to be installed on a roof of a building, there are known, for instance, a manner of installing a fixing member or a trestle on a roof of a building and fixing a solar cell module on said fixing member or trestle and a manner of providing a solar cell module comprising a photovoltaic element integrated with a roofing member such as a roof tile or a metal roofing member and installing said solar cell module on a sheathing roof board.
The solar cell module is usually structured such that electric wirings comprising a cable are connected to the rear face side opposite the light receiving face side so as to output electric power. And, generally, a plurality of solar cell modules having such structure are arranged and they are electrically connected with each other by way of electric-wiring. The power outputted from a plurality of solar cell strings each comprising a plurality of solar cell modules being electrically connected with each other are guided into a connection box, where they are connected in parallel to each other. The power outputted from the connection box is guided into a so-called inverter as a power converter, where it is converted into an alternate current, followed by being used in a load device of a domestic power-receiver or by back-flowing to an electric power company. Such inverter is provided inside the house or it is provided outdoors in view of heat or noise generated thereby.
In the case where the inverter is provided inside the house, for solar cell modules arranged on a sheathing roof board constituting a roof base member or a previously formed roof comprising a roofing member laid on a roof base member, in order to electrically connect electric wirings from said solar cell modules to the connection box and the inverter, the electric wirings are necessary to be led-in inside the house. In order to facilitate this work, Japanese Patent No. 2565611 proposes that a ventilation layer is provided between a sheathing roof board and a roof panel, an power output cable from a solar cell is passed through the space of the ventilation layer, followed by introducing into a house on the ridge portion side.
However, in such conventional manner of leading-in the electric wirings inside the house, there is a disadvantage such that penetration holes are necessary to be provided at a waterproofed means provided at a ridge portion or the like of a building and which is situated above the indoor space, namely, at the roof face situated at the ridge portion, where the waterproof reliability of the building is likely to be deteriorated. Further, in the conventional case where the inverter is installed outdoors, there is a disadvantage such that after the electric wirings are once led-in inside the building, they are necessary to be taken out to the outside, where the arrangement of the electric wirings is complicated. In addition to this, there are also a disadvantage such that the wiring works are required to be conducted at the time of roof covering, and because of this, previous preparation of day""s schedule and the like is necessary.
A principal object of the present invention is to eliminate the foregoing disadvantages found in the prior art and to provide a solar cell-bearing roof comprising a solar cell module sealed therein and which enables one to draw electric wiring from said solar cell module to the without deteriorating the waterproof reliability of the roof and a method for installing said roof.
Another object of the present invention is to provide a solar cell-bearing roof comprising a solar cell module sealed therein and which enables one to readily install said solar cell-bearing roof on a building and readily check the electric system of the roof installed on the building.
A further object of the present invention is to provide a solar cell-bearing roof comprising a solar cell module which is installed on a building such that electric wiring from the solar cell module of the roof is wired outside the building so that the waterproof ability and the resistance to thunderbolt are ensured.
A further object of the present invention is to provide an execution method of installing the above solar cell-bearing roof on a building.
A further object of the present invention is to provide a power generation system comprising the above solar cell-bearing roof.